B1142

Steering Column Switches

Pinpoint Test E: DTC B1142:29

Normal Operation

Battery voltage is sent to the ignition switch from the Battery Junction Box (BJB) fuse 28 (15A). When placed in ACC, RUN or START, the ignition switch sends fused battery voltage along 1 of 3 circuits to the Body Control Module (BCM). Microprocessors in the BCM (Body Control Module) continuously monitor the ignition switch state.

- DTC B1142:29 (Ignition Status 1: Signal Invalid)- this DTC sets when the BCM (Body Control Module) does not receive a valid ignition state signal during the BCM (Body Control Module) self-test.

This pinpoint test is intended to diagnose the following:

- Wiring, terminals or connectors

- Ignition switch

- BCM (Body Control Module)

PINPOINT TEST E : DTC B1142:29

NOTICE: Use the Flex Probe Kit for all test connections to prevent damage to the wiring terminals. Do not use standard multi-meter probes.

E1 CHECK THE IGNITION SWITCH STATE (IGN_SW_STATE) PID

- Ignition ON.

- Enter the following diagnostic mode on the scan tool: DataLogger- BCM (Body Control Module).

- Monitor the IGN_SW_STATE PID while turning the ignition switch through all 4 positions (OFF, ACC, RUN and START).

Does the PID match each ignition switch position?

Yes
GO to E5.
No
GO to E2.

E2 CHECK THE ACC CIRCUIT FOR AN OPEN OR SHORT TO VOLTAGE

- Ignition In ACC.

- Monitor the IGN_SW_STATE PID with the ignition switch in the ACC position.

Does the PID display "Acc"?

Yes
GO to E3.
No
If the PID displays "Off" or "Unknown", REPAIR circuit CDC33 (VT/GN) for an open. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.

If the PID displays "Run" or "Start", REPAIR circuit CDC34 (WH/OG) (RUN) or CDC35 (BU/WH) (START) for a short to voltage. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.

E3 CHECK THE RUN CIRCUIT FOR AN OPEN OR SHORT TO VOLTAGE

- Ignition ON.

- Monitor the IGN_SW_STATE PID with the ignition switch in the RUN position.

Does the PID display "Run"?

Yes
GO to E4.
No
If the PID displays "Off" or "Unknown", REPAIR circuit CDC34 (WH/OG) for an open. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.

If the PID displays "Acc" or "Start", REPAIR circuit CDC33 (VT/GN) (ACC) or CDC35 (BU/WH) (START) for a short to voltage. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.

E4 CHECK THE START CIRCUIT FOR AN OPEN OR SHORT TO VOLTAGE

- Monitor the IGN_SW_STATE PID with the ignition switch in the START position.

Does the PID display "Start"?

Yes
GO to E5.
No
If the PID displays "Off" or "Unknown", REPAIR circuit CDC35 (BU/WH) for an open. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.

If the PID displays "Acc" or "Run", REPAIR circuit CDC33 (VT/GN) (ACC) or CDC34 (WH/OG) (RUN) for a short to voltage. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.

E5 CHECK FOR CORRECT BCM (Body Control Module) OPERATION

- Disconnect: All BCM (Body Control Module) Connectors.

- Check BCM (Body Control Module) connectors for:
- corrosion

- damaged pins

- pushed-out pins


- Connect: All BCM (Body Control Module) Connectors.

- Make sure the connectors are seated correctly, then carry out a BCM (Body Control Module) self-test.

- Operate the system and verify the concern is still present.

Is the concern still present?

Yes
INSTALL a new BCM (Body Control Module). REPEAT the self-test. TEST the system for normal operation.
No
The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.